如何在视图中的任何位置检测到点击？

Question

I have a tutorial for my app, which should display only the first time the app is opened and should be tapped to dismiss.

I am initializing a UITapGestureRecognizer in my viewDidLoad:

tapper_tut = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleSingleTap:)];
tapper_tut.cancelsTouchesInView = FALSE;
[self.view addGestureRecognizer:tapper_tut];

and I have an IBAction to detect the tap and set the tutorial to hidden:

- (IBAction)dismiss_tut{
    if (????????????????) {
        _tutorial.hidden = YES;
    }
}

But I have no idea what to put in the if statement condition, or if this is even that right way to go about this.

How would I dismiss a UIImageView on a tap?

Answer 1

UITapGestureRecognizer *gr = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
[self.view addGestureRecognizer:gr];
// if not using ARC, you should [gr release];
// mySensitiveRect coords are in the coordinate system of self.view


- (void)handleGesture:(UIGestureRecognizer *)gestureRecognizer {
    CGPoint p = [gestureRecognizer locationInView:self.view];
    if (CGRectContainsPoint(mySensitiveRect, p)) {
        NSLog(@"got a tap in the region i care about");
    } else {
        NSLog(@"got a tap, but not where i need it");
    }
}

Answer 2

You can make viewDidLoad like this

- (void)viewDidLoad 
  { 
      [super viewDidLoad];
      self.view.backgroundColor = [UIColor whiteColor];

      /* Create the Tap Gesture Recognizer */
      self.tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
                                   action:@selector(handleTaps:)]; 

     /* The number of fingers that must be on the screen */
      self.tapGestureRecognizer.numberOfTouchesRequired = 1;

     /* The total number of taps to be performed before the gesture is recognized */
      self.tapGestureRecognizer.numberOfTapsRequired = 1;

     /* Add this gesture recognizer to the view */
     [self.view addGestureRecognizer:self.tapGestureRecognizer];
  }

To detect the taps you can make the method like this.

- (void) handleTaps:(UITapGestureRecognizer*)paramSender
  {
      NSUInteger touchCounter = 0; 
      for (touchCounter = 0;touchCounter < paramSender.numberOfTouchesRequired;touchCounter++)
      {
            CGPoint touchPoint =[paramSender locationOfTouch:touchCounter inView:paramSender.view];
            NSLog(@"Touch #%lu: %@",(unsigned long)touchCounter+1, NSStringFromCGPoint(touchPoint));
      }
  }

Answer 3

you have to declare .h file as "UIGestureRecognizerDelegate"

you have getting tap of gesture as two way as given below steps.

1) Call delegate method of GestureRecognizer (not given action )

UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:nil]; // not given  action.
recognizer.numberOfTouchesRequired=1;// here how many tap you want set it 
[self.view addGestureRecognizer:recognizer];
recognizer.delegate = self;

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
 {
     //whatever you want write code here
    return NO;
  }

2) given action

 UITapGestureRecognizer *oneTouch=[[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(Addphoto)];
 [oneTouch setNumberOfTouchesRequired:1];
 [self.view addGestureRecognizer:oneTouch];

 -(IBAction)Addphoto
 {
     //whatever you want write code here
 }

may be it will help .

Answer 4

I think u need to detect the first time launch of the application which u can do with following

![[NSUserDefaults standardUserDefaults] boolForKey:@"HasLaunchedOnce"]

Put this in your if statement .